note 12284 deleted from language.oop by victor

In php objects are stored as associative arrays. Empty arrays are false by definition (most likely from PHP's perl heritage). I believe what you are looking for is: $var = new Cart(); if(!isset( $var )) echo "failure"; This is a very handy feature for writing hard to read code (i.e. job security). But seriously, it is useful for distinguishing null from zero, or in this case: the object was not created succesfully ( isset($var) returns false, the null case) -from- the object was created but not successfully initialized ( isset($var) returns true but $var is false, the zero case)